1. Field of the Invention
This invention relates to packaging apparatus and methods. Particularly, this invention relates to a system and method for use at the infeed end of a cartoning machine to control the infeed of articles such as beverage cans thereinto during a stoppage or shutoff procedure. The infeed control system and method of the present invention simplifies and speeds the stoppage or shutdown of such packaging machines.
2. Background Information
Various machines have been utilized to package a variety of products. Although many of these machines operate continuously and at very high speeds they must all be periodically shut down for routine maintenance and for changes in the processed product or packaging. Shut down and clean out is typically performed by hand and is a relatively slow process. Manual shut down procedures significantly reduce the overall speed and productivity of the machine over the course of its operative life. And, because such procedures are labor intensive, they increase the overall cost of operating the machine.
The typical packaging machine utilizes a selection or metering mechanism to process an ungrouped stream or line of infeed articles into groups of articles having a predetermined size and orientation. Flight bars are often used in such mechanisms. Many of these machines rely on pressure or surge from articles located upstream on the article infeed line to maintain proper flow of articles into the selection mechanism. During a shut down or clean out procedure, the input of articles is terminated and infeed surge pressure is lost. Once back pressure is lost, the terminal article or group of articles will likely not be processed properly, and malformed or incompletely formed groups can result. In the case of selection mechanisms utilizing flight bars, spearing of articles such as cans may occur. Spearing results in exploding cans which is dangerous and costly to clean up. The terminal group of articles in the infeed line must therefore be removed manually to avoid these problems. Manual removal of the infeed cans leads to a requirement for manual manipulation of for example intermediate formed groups and packaging media located downstream on and sometimes deep within the packaging machine. On large high speed machines the net loss of processing time due to manual clean out procedures is significant. Manual procedures performed on large high speed equipment also poses safety problems.
Insofar as is known, no apparatus or method has been developed or proposed which has solved the problem of accomplishing machine shut down and clean out quickly, easily, safely and automatically. In view of the limitations and shortcomings of prior art methods and apparatus, it is an object of this invention to provide a system and method for use with a continuous high speed packaging machine which minimize shut down and clean out time. A particular object of this invention is to provide a system and method which are useable with packaging machines that rely on pressure from upstream articles to infeed articles into a selection or metering mechanism or section. A final object of this invention is to provide a system and method which are useable with a variety of packaging machine designs and with a variety of article and article group types and sizes.